The unmethylated and unconverted human control DNA of the EpiTect PCR Control DNA Set allows to check that primers designed for the specific detection of unmethylated and converted DNA (U-converted DNA), and for methylated, converted DNA (M-converted DNA) do not bind to untreated genomic DNA.*
In case bisulfite conversion was not complete, leaving certain unmethylated C residues unconverted, false positives would result if the primer specific for M-converted DNA binds to untreated gDNA.
This control DNA can also be used to check conversion efficiency during bisulfite treatment.
*(Summary of principle: Methylation of DNA occurs on cytosine residues, especially on CpG dinucleotides enriched in small regions of DNA. Incubation of target DNA with sodium bisulfite, using e.g. EpiTect Bisulfite Kits, results in conversion of unmethylated cytosine residues into uracil, leaving methylated cytosines unchanged).